Examples of a display device equipped with a touch sensor in recent years include the following: an upper plate added type (add-on type) that is obtained by preparing a display device and a touch panel individually and thereafter attaching the touch panel to the display device; and an upper plate integrated type (on-cell type) that is obtained by forming a touch sensor directly on a surface of an upper glass substrate of a display device. The display device of the upper plate integrated type has a smaller thickness as compared with the display device of the upper plate added type, and still further, a display device of a touch sensor integrated type has been developed as a display device of a further thinner type.
For example, Patent Document 1 discloses a display device of a touch sensor integrated type that includes: a plurality of gate lines and a plurality of data lines that intersect with one another; a plurality of pixel electrodes formed in areas defined by the gate lines and the data lines intersecting with one another; and a plurality of common electrodes that are formed so as to overlap with the pixel electrodes, respectively. In this display device, the common electrodes also function as common electrodes of the display, as well as touch drive electrodes and touch sensing electrodes that compose a touch sensor.